FAIR VALUE MEASUREMENT - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Carrying Amount
Liabilities:
Debt, fair value	$ 26,203,749	$ 26,328,025
Estimated Fair Value
Liabilities:
Debt, fair value	25,040,459	26,449,620
Fair Value, Inputs, Level 2 [Member] \| Carrying Amount \| Credit facility debt \| CSC Holdings
Liabilities:
Debt, fair value	8,318,764	8,495,611
Fair Value, Inputs, Level 2 [Member] \| Carrying Amount \| Secured Debt [Member] \| CSC Holdings
Liabilities:
Debt, fair value	1,716,600	1,706,997
Fair Value, Inputs, Level 2 [Member] \| Carrying Amount \| Senior guaranteed notes and senior secured notes \| CSC Holdings
Liabilities:
Debt, fair value	8,078,369	8,077,372
Fair Value, Inputs, Level 2 [Member] \| Carrying Amount \| Senior notes \| CSC Holdings
Liabilities:
Debt, fair value	7,957,142	7,950,241
Fair Value, Inputs, Level 2 [Member] \| Carrying Amount \| Notes payable and supply chain financing \| CSC Holdings
Liabilities:
Debt, fair value	132,874	97,804
Fair Value, Inputs, Level 2 [Member] \| Estimated Fair Value \| Credit facility debt \| CSC Holdings
Liabilities:
Debt, fair value	8,366,750	8,546,438
Fair Value, Inputs, Level 2 [Member] \| Estimated Fair Value \| Secured Debt [Member] \| CSC Holdings
Liabilities:
Debt, fair value	1,727,051	1,741,710
Fair Value, Inputs, Level 2 [Member] \| Estimated Fair Value \| Senior guaranteed notes and senior secured notes \| CSC Holdings
Liabilities:
Debt, fair value	7,610,688	8,180,813
Fair Value, Inputs, Level 2 [Member] \| Estimated Fair Value \| Senior notes \| CSC Holdings
Liabilities:
Debt, fair value	7,203,109	7,883,071
Fair Value, Inputs, Level 2 [Member] \| Estimated Fair Value \| Notes payable and supply chain financing \| CSC Holdings
Liabilities:
Debt, fair value	132,861	97,588
Fair Value Measured on a Recurring Basis \| Fair Value, Inputs, Level 1 [Member]
Assets:
Investment securities		2,161,937
Prepaid forward contracts \| Fair Value Measured on a Recurring Basis \| Fair Value, Inputs, Level 2 [Member]
Assets:
Derivative asset	0	0
Liabilities:
Derivative liability	60,868	161,942
Interest rate swap contracts \| Fair Value Measured on a Recurring Basis \| Fair Value, Inputs, Level 2 [Member]
Assets:
Derivative asset	53,539	2,993
Liabilities:
Derivative liability	30,084	118,432
Money market funds \| Fair Value Measured on a Recurring Basis \| Fair Value, Inputs, Level 1 [Member]
Assets:
Money market funds	$ 131,259	$ 100,015

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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